Oh dear. Judging by those pics you posted you've already gone a long way to the "dark side"
You CAN do astrophotography with your 8". As others have said, down that road you'll encounter challenges and costs such as:
- Need rings and mount (HEQ5Pro can do what you want EQ6/NEQ6/AltAzEQ6 better)
- Probably need coma corrector, may not initially
- Likely need guidescope and guide camera to get >1min pics
- Will need access to dark sky site, but can do lots from suburbia too
- Will need laptop for guiding, camera control eventually then camera/guiding control software as get serious
- Likely to want to buy processing software
- Auto-focus is a huge boon, but again, has costs
- Can't do visual while using your dob for AP
- Will lose lots of subs to guiding issues and have to be really patient re focus etc
So for a newt system, perhaps:
$1600 HEQ5Pro
$100 Rings
$600 Guiding package and camera, dovetail, rings (less if used a 50mm finder/guider)
$1000 Laptop
Alternatively, for an ED80 setup, you probably will have backfocus for an off-axis guider but have the extra cost of an additional OTA. LOTS easier to guide at the smaller focal length.
One big benefit of the 8" is its light sucking power, so subs don't have to be as long.
Many of pics here were with an 8" F5 on HEQ5Pro when I was starting out if of any use:
https://picasaweb.google.com/UserRob...isibleFrom27S#